text: ["Wisdom teeth are vestigial third molars that human ancestors used to help in grinding down plant tissue. The common postulation is that the skulls of human ancestors had larger jaws with more teeth, which were possibly used to help chew down foliage to compensate for a lack of ability to efficiently digest the cellulose that makes up a plant cell wall. As human diets changed, smaller jaws gradually evolved, yet the third molars, or "wisdom teeth", still commonly develop in human mouths."](_URL_0_) Many of our ancestors would have been dead by the time they happened and/or have already produced offspring, so the evolutionary pressure to stop growing them would be lessened. (It's an advantage to have healthy, experienced older people around, so there is still some pressure.)